Electric-circuit connecter



Ot. 29, 1929. A F, F, GlLsoN 1,733,591

ELECTRIC CIRCUIT CONNECTER Filed April 29. 1926 fr/7J. V 22 NE vv yWAI/ry.

Patented oct. 29, 1929 UNITED l'STATES PATENT OFFICE ALBERT F. F.GILSON, OF ORADELL, NEW JERSEY, ASSIGNOR T BELL TELEPHONE- iLABORATORIES, INCORPORATED, OF NEW YORK, N.' Y., A CORPORATION 0F NEWELECTRIC-CIRCUIT CONNECTER Application filed April 29,

This invention relates to circuit connecters of the plug and socket typeand more particularly to receptacles or sockets for plugs of vacuum tubebases.

Heretofore, sockets for push type vacuum tubes consisted in general ofxadisc or block having apertures to receive the terminal pins' of a vacuumtube base, and a plurality of' tion in which substantially the wholesur-v face of the terminal pin on the vacuum tube base is in engagementwith the contact.

A further object of the invention is vto provide an arrangement of thecontacts whereby the necessity of accurate dimensioning of the elementsis overcome.

In accordance with this invention, an insulating block or socket isprovided with a plurality of chambers or pockets arranged about the axisof the socket. These chambers are provided with recesses therein torecelve closely wound wire helical contacts havlng one end of largerdimension than the other, and a terminal at one endproJecting through-the side of the socket. These contacts are normally slightly longerthan the chambers in which they are seated, so that an insulating memberhaving apertures corresponding with the helical contacts, but of smallerdiameter, may be fastened to one end of the socket to compress thecontacts and mlsahne the intermediate turns ofthe helices.

lThis arrangement provides a compact socket for push type vacuum tubes,in which the terminal pins on the vacuum tube base may be inserted inthehelical contacts to 1926. Serial No. 105,389.

realine the turns of the helices and provide large surface frictionalcontact. Furthermore, by such -an arrangement the vacuum tube isheldsecurely in the socket since the turns of each helix tend to windaround thel terminal pins. l

A feature of the invention is the misalinei ment of the intermediateportion of the helical contact to insure a positive engagement of alarge portion of the contact with the terminal pin of the vacuum tubebase.

Another feature is the cooperating action of the guiding portion of thehelical cont-act with the misalined turns hereof, to prevent irregularpositioned terminal pins distorting the contacts.

These and other features of the inventionl v will be apparent from thefollowing detailed description in connection with the accompanyingdrawing, in which Fig. 1 illustrates in cross section, a push typesocket made in accordance with this invention; Fig. 2, is a plan view ofFig. 1 with a portion broken away to show the relative position of oneof the contacts; Fig. 3 is the same as Fig. 1 with the vacuum tubeinserted in the socket; Fig. 4' is a modified form of the socketshown inFig. 1; and Fig. 5 is an enlarged view 'of a modified contact made inaccordance with this invention.

Referring particularly to Fig. 1, the push type socket of thisinvention, comprises a block or receptacle 10, preferably of moldedinsulating material, such as hard rubber or bakelite, which is providedwith cylindrical internal chambers 11. The chambers 11, which areusually` four in number, are arranged at four corners of a square aroundthe axis of the receptacle 10, and are rovided at the lower end with arecess 12, o smaller diameter. Arranged within each chamber is a closelywound wire helical contact 13, having the lower end turns oflsubstantially the samev diameter as the recess 12 to provide a force itconnection between the contact-13 and the receptacle 10. These contactsare normally longer than the length of the 'chamber 11 and the recess12, so that before-assembly they project beyond the upper surface of thereceptacle 10'. The upper end of each contact is provided with anoutwardly tapered portion to provide guiding means for irregular spacedterminal pins of a vacuum tube base. Attached tothe end turn of thetapered portion of the contact 13 is a metallic terminal 14 whichprojects through the side of the receptacle at right angles to the axisof the contact 13 and is preferably seated in a groove in the uppersurface of the receptacle 10. A

disc 15 having apertures 16, of slightly smaller diameter than thetapered portions of the contacts 13, is arranged to close the open endof the receptacle 10 with the apertures 16 coaxial with the ends of thecontacts 13. This disc compresses the helical contacts 13 within thechambers 11 due to the difference between the length of the chamber 11and the helical contact 13, and thereby misalines the intermediate turnsof the helical contacts as shown at 17. The disc 15 may be fastened tothe receptacle 10 in any suitable manner, for instance, as shown in thedrawing. by a screw 18 passing through the axis of the disc and thereceptacle and being fastened at the lower end by a nut 19 located inthe counter-sunk portion 2O of the receptacle 10. This arrangementprovides a compact socket in which the misalinement of the intermediateturns of the helical contacts provides a large surface contact for theterminal pins 21 of the vacuum tube base 22. This arrangement alsoovercomes the necessity of accurate dimensions of the helical contact'13and the terminal pin 21, since the offset or misalined portion 17compensates for small differences of diameters between the terminal pin21 and the contact 13. Furthermore, the tapered portionadjacent theapertures 16 in the disc provides a guiding means for centering theterminal pins 21 of the vacuum tube base 22. The socket of thisinvention is also arranged to receive the present type of vacuum tubes,in which two of the terminal pins are of'larger diameter than the othertwo, to

prevent the wrong engagement of the terminal pins with their respectivecontacts. This is clearly shown in Fig.- 2.

Referring to Fig. 3, the vacuum tube socket of this invention is shownwith the terminal pins 21 inserted in the contacts 13, to illusltratethe large surface Contact obtained with the improved helical contact ofthis invention. The insertion of the terminal pins into the helicalcontact tends to aline each adjacent turn of the contact and exert atwisting motion around the terminal pin 21, thereby insuring largesurface and positive contact.

A modified form of socket is shown in Fig. 4, in which the receptacle 10is provided with apertures 23 corresponding to the apertures 16 in thedisc 15 of Fig. 1. The chambers 11 are open at their lower end toreceive the helical contacts 13 with the tapered portion of the contactfitted into a recess coaxial with the apertures 23. The contactterminal'lc is with a separable terminal extension soldered or affixedto either end of the helix, it is a parent that modifications can bemade in t e structure as shown in Fig. 5, in which the terminalandhelical contacts are integral. In this arrangement the terminal 25 isformed by .providing a rightangle continuation of the wire helix 13 andforming a loop 26 at the end thereofto which external connections may bemade. Furthermore, the invention is not limited to a vacuum tube socketsince other receptacles may be made with the novel helical contactarrangement without departing from the spirit of the invention asdefined in the appended claims.

lVhat is claimed is:

1. An electric terminal socket comprising a `helical Contact member anda supporting member therefor, said helical member having an intermediateportion normally offset with respect to the end portions thereof.

2. An electric terminal socket comprising a wire helix, a supportingmember therefor, and an apertured member, said helix having a guidingportion adjacent said apertured member and an OH'set portion.

3. An electric terminal socket comprising a wire helix, a supportingmember therefor, and a member having an openin therein, said helixhaving the ends thereo in alinement with the opening` in said member,and a portion misalined with respect to said opening.

4. An electric terminal socket comprising a wire helix, a supportingmember therefor, and a member having an opening therein, said helixhaving the ends thereof in alinement with the opening in said member andan intermediate portion misalined with respect to said opening, theturns at one end being of larger diameter than the turns at the otherend.

5. An elm tric terminal socket comprising a supporting member a wirehelix, therein, and means bear'ig on said helix to offset a portionthereof.

. 6. An electric terminal socket comprising a supporting block, anapertured block, and a plurality' of closely wound wire helices havingmisalined turns compressed between said blocks.

7. An electric terminal socket comprising an insulating block, anapertured insulating block, a plurality of wirehelices` between saidblocks, and fastening means engaging said blocks to misaline the turnsof said helices.

8. An electric terminal socket comprising an insulating supportingmember, a plurality of closely Wound wire helices therein, said helicesnormally projecting beyond said member, and a plate closing saidsupporting member, said plate engaging said helices to misaline theturns thereof.

9. A socket for a vacuum tube having terminal pins, said socketcomprising a receptacle of insulating material, l resilient Wire helicesin said receptacle, a plate for said receptacle, and means for fasteningsaid plate thereto, said helices being compressed and misalined in saidreceptacle by said plate and adapted to be realined by the insertion ofsaid terminal pins therein.

10. A socket for a vacuum tube having terminal pins, said socketcomprising a receptacle of insulating material having internal chambers,resilient Wire helices in said chambers, a member having perforationstherein, a portion of said helices being misalined with respect to saiderforations and adapted to be realined by t e insertion of said terminalpins of said tube.

In Witness whereof, I hereunto subscribe my name this 27 day of April,A. D., 1926.

ALBERT F. F. GILSON.

